fix(auth): allow admins to change any username including their own

services/api/internal/auth/pgstore.go

@@ -340,8 +340,9 @@ func (s *PgStore) UpdateUser(ctx context.Context, id uuid.UUID, upd UserUpdate)
 		r := string(*upd.Role)
 		role = &r
 	}
-	return scanUser(s.q.QueryRow(ctx, `
+	u, err := scanUser(s.q.QueryRow(ctx, `
 		UPDATE users SET
+			username = COALESCE($8, username),
 			display_name = CASE WHEN $2 THEN $3 ELSE display_name END,
 			role = COALESCE($4::user_role, role),
 			is_blocked = COALESCE($5, is_blocked),
@@ -349,7 +350,11 @@ func (s *PgStore) UpdateUser(ctx context.Context, id uuid.UUID, upd UserUpdate)
 			token_version = token_version + CASE WHEN $6 THEN 1 ELSE 0 END,
 			updated_at = now()
 		WHERE id = $1
-		RETURNING `+userColumns, id, setName, name, role, upd.IsBlocked, upd.RevokeTokens, upd.ReviewsUploads))
+		RETURNING `+userColumns, id, setName, name, role, upd.IsBlocked, upd.RevokeTokens, upd.ReviewsUploads, upd.Username))
+	if isUniqueViolation(err) {
+		return User{}, ErrUsernameTaken
+	}
+	return u, err
 }
 
 // ResetPassword реализует Store.